Puget Sound and the Strait of Georgia stretch 290 km south from the Canadian border to Olympia, WA. Tidal variations provide expansive intertidal habitats for shorebirds and waterfowl. Large bays and estuaries characterize the northern Puget Sound. The principal rivers (Nooksack, Samish, Skagit, Stillaguamish, Nisqually and Snohomish) formed extensive floodplains that support palustrine marshes, riparian corridors, and expansive agricultural zones. Principal crops grown in the region include barley, cold leaf crops, carrots, potatoes, and hay. Fallow fields are utilized heavily by staging and wintering waterfowl. In the northern Puget Sound, eelgrass beds are extensive in Skagit, Padilla, and Samish Bays, while Port Susan, Bellingham and Lummi Bays support tidal marshes with less eelgrass. The “upper intertidal zone” in all of these areas has been largely lost due to diking and draining activities, primarily to convert these areas to agricultural fields. The middle reach of Puget Sound is heavily altered. The Seattle-Tacoma Metropolitan area has a population approaching 8 million people. The Puget Sound has one of the highest population growth rates in the country. The Hood Canal and Nisqually River Valley are the primary wetland habitats in the southern Puget Sound.
State protected wildlife areas include Washington Department of Fish and Wildlife lands at Skagit, Lake Terrell, Nisqually, Sequim, and Snoqualmie. Federally protected lands include Nisqually River Estuary, Dungeness Spit, and Padilla Bay. The northern bays of Puget Sound support nearly 80% of western Washington’s wintering waterfowl. The loss of freshwater and estuarine wetland habitat in the region has shifted waterfowl habitat dependency to agricultural lands in the past 100 years, particularly in the Skagit Delta. Mallard, wigeon, and northern pintail make up nearly 90% of the total puddle ducks wintering in the region. The heaviest concentrations occur in Port Susan, Skagit, and Padilla bays. Marine habitats in the Puget Sound, along with similar habitats in coastal Washington, account for 46% of the goldeneyes and 49% of the buffleheads wintering in the Pacific Flyway. Urbanization, with its associated loss of wetlands and agricultural lands, degradation of existing wetlands, and lowered water quality, will be the greatest threat to these waterfowl populations.
Importance to waterbirds
The Skagit River Delta and Samish Bay support over 30,000 Wrangel Island snow geese and hundreds of thousands of ducks during the migration and wintering periods. Waterfowl counts exceeding one million birds have become increasingly common in the Skagit and Samish bays. Padilla Bay winters over 10,000 Pacific brant, the largest wintering population of this species north of Mexico (Ball et al. 1989). The Skagit Delta is also an important region for more than 700 wintering trumpeter swans. These swans, along with 1,500 tundra swans, forage in grain fields, fallow potato fields, and tidal estuaries. The Olympic Mountains and rough coastal areas of the Outer Sound support the densest U.S. breeding population of harlequin ducks. Hydroelectric dams, deforestation, and development have threatened this Mergini species through much of its nesting range in the Cascade and Sierra Nevada Mountains. The Hood Canal supports numerous Barrow’s and common goldeneye, in addition to wintering white-winged and surf scoters.
Washington's Pacific Coast (not including Puget Sound) is a sloping beachfront cut by Grays Harbor and Willapa Bay. Willapa Bay constitutes one of the largest and most pristine estuaries in the U.S. Its shallow contours make it unusable as a deep-water port and the Bay supports the state’s largest commercial shellfish beds. A threat to this habitat is the introduction of smooth cordgrass. This invasive weed is choking out important mudflats and aquatic beds. Efforts are underway to assist the U.S. Fish and Wildlife Service and the Washington Department of Fish and Wildlife to control smooth cordgrass in Willapa Bay and other coastal habitats. Grays Harbor is fed by several lentic systems including the Chehalis River, which has a large expanse of bottomland habitats.